Improving Efficiency in Matching Markets with Regional Caps: The Case of the Japan Residency Matching Program

In an attempt to increase the placement of medical residents to rural hospitals, the Japanese government recently introduced "regional caps" which restrict the total number of residents matched within each region of the country. The government modified the deferred acceptance mechanism incorporating the regional caps. This paper shows that the current mechanism may result in avoidable ineffciency and instability and proposes a better mechanism that improves upon it in terms of effciency and stability while meeting the regional caps. More broadly, the paper contributes to the general research agenda of matching and market design to address practical problems.